Swedish researchers have developed a unique composite material, plasmonic plastic, that can be 3D printed and used to create optical hydrogen sensors. This material could play a crucial role in the transition to greener energy and industry.
Plasmonic plastic and its optical properties
THE plasmonic plastic is a composite material consisting of a polymer and plasmonically active colloidal metal nanoparticles. Plasmonic particles interact strongly with light, making them useful for various applications, such as optical components for medical sensors, medical treatments, photocatalysis to control chemical processes, and various types of gas sensors.
The researchers of theChalmers University of Technology worked for six years on this project, seeking to sustainably produce large quantities of plasmonic metal nanoparticles and fabricate three-dimensional plasmonic objects. Plastic was chosen because of its properties, including its ability to be formed into almost any shape, its affordability, its potential for scaling, and its compatibility with 3D printing.
3D printed hydrogen sensors
The researchers chose to focus on the plasmonic sensors capable of detecting hydrogen as a target application for this type of composite material. They have thus opened the way to a new approach in the field of optical sensors based on plasmons, by being able to print them in 3D.
Professor Christoph Langhammer, who led the project, explains that the interaction between the polymer and the nanoparticles is a key factor in making these sensors from plasmonic plastic.
This type of plastic not only allows for additive manufacturing (3D printing) and scaling of the material manufacturing process, but it also has the important function of filtering out all but the smallest molecules, such as the hydrogen molecules that we wish to detect. This prevents the sensor from becoming deactivated over time.
Many possible applications
While reducing the use of plastics is desirable in general, there are many advanced engineering applications that are only possible due to the unique properties of plastics. Plasmonic plastics could help harness the versatile toolbox of polymer technology to design new gas sensors, healthcare applications and wearable technologies, for example.
The material could even inspire artists and fashion designers because of its attractive and adjustable colors. Professor Christoph Langhammer emphasizes that production of the material can be scaled up, relies on environmentally friendly and resource-saving synthesis methods to create the nanoparticles, and is easy to implement. artwork.
Plasmonic plastic consists of a polymer, such as amorphous Teflon or PMMA (plexiglass), and colloidal nanoparticles of a metal distributed evenly within the polymer. At the nanoscale, metal particles acquire useful properties such as the ability to interact strongly with light. This effect is called plasmons. The nanoparticles can then change color if their environment changes or if they modify themselves, for example following a chemical reaction or by absorbing hydrogen.
Dispersing the nanoparticles in the polymer protects them from the environment, because large molecules are not able to move through the polymer like hydrogen molecules, which are extremely small. The polymer acts as a molecular filter. This means that a plastic plasmonic hydrogen sensor can be used in more demanding environments and will age less. The polymer also makes it easy to create three-dimensional objects of very different sizes that exhibit these interesting plasmonic properties.
This unique interaction between polymer, nanoparticles and light can be used to achieve personalized effects, potentially in a wide range of products. Different types of polymers and metals bring different properties to the composite material, which can be tailored to a particular application.
Plasmonic plastic, developed by Swedish researchers, is a unique composite material that can be 3D printed and used to create optical hydrogen sensors. This material could play an important role in the transition to greener energy and industry, as well as many other applications, such as healthcare, wearable technology and even art and fashion.
For a better understanding
1. What is plasmonic plastic?
Plasmonic plastic is a composite material composed of a polymer and plasmonically active colloidal metal nanoparticles. It has unique optical properties and can be 3D printed.
Plasmonic plastic-based hydrogen sensors detect hydrogen molecules through the interaction between the polymer and nanoparticles. The nanoparticles change color when they come into contact with hydrogen, signaling the presence of the gas.
3. Why did researchers choose to focus on hydrogen sensors?
The researchers chose to focus on hydrogen sensors because they are needed to accelerate the development of medicine and the use of hydrogen as a carbon-free alternative to fossil fuels.
4. What are other possible applications of plasmonic plastic?
Plasmonic plastic can be used to design new gas sensors, healthcare applications, wearable technologies, and even inspire artists and fashion designers due to its attractive and tunable colors.
5. What are the advantages of plasmonic plastic?
Plasmonic plastic is cost-effective, easy to shape, compatible with 3D printing, and can be produced at scale. Additionally, it relies on environmentally friendly and resource-efficient synthesis methods to create the nanoparticles.
The “Plastic Plasmonics” research project received funding of 28.9 million Swedish crowns from the Swedish Foundation for Strategic Research and was completed in summer 2022.
The article “Bulk-Processed Plasmonic Plastic Nanocomposite Materials for Optical Hydrogen Detection“, published in Accounts of Chemical Research on July 4, 2023, reports on research that, between 2017 and 2022, has been described in almost 40 different publications.
Main illustration caption: 3D printed sensing element from plasmonic plastic for use in an optical hydrogen sensor. This particular element contains palladium nanoparticles, which gives it its gray color. Photo: Malin Arnesson/Chalmers
[ Rédaction ]